<!DOCTYPE html>
<html>
  <head>
    <title>Messaging Test</title>
    <meta http-equiv="content-type" content="text/html; charset=utf-8">
    <meta name="viewport" content="width=320, user-scalable=no">
  </head>
  <body>
    <p>Messages received from React Native: 0</p>
    <p>(No messages)</p>
    <button type="button">
      Send message to React Native
    </button>
  </body>
  <script>
    var messagesReceivedFromReactNative = 0;
    document.addEventListener('message', function(e) {
      messagesReceivedFromReactNative += 1;
      document.getElementsByTagName('p')[0].innerHTML =
        'Messages received from React Native: ' + messagesReceivedFromReactNative;
      document.getElementsByTagName('p')[1].innerHTML = e.data;
    });

    document.getElementsByTagName('button')[0].addEventListener('click', function() {
      window.postMessage('"Hello" from the web view');
    });
  </script>
</html>
